摩卡测试 TypeScript 与全局 scope 中定义的类型

Question

I'm currently putting together a test framework for a legacy application that has many types.ts files that define types without any imports/exports in the top level of the file. For example, we have a Pills/types.ts file that contains only

interface Pills {
 id: number,
 // more properties
}

According to the TypeScript documentation , without an imports/exports, the file is considered a module and is a part of the global scope. Any file that uses the Pills type uses it without explicitly importing the type. This currently works fine in our web application, which is running as a webpack bundle.

However, when I try to run a test using mocha , which runs on NodeJS, I get the following error:

app/javascript/components/HardwareTestReports/table.tsx(18,16): error TS2304: Cannot find name 'Pill'.
app/javascript/components/HardwareTestReports/table.tsx(106,56): error TS2304: Cannot find name 'Pill'.

Is this because mocha runs on NodeJS, which require files to explicitly declare exports/imports?

My .tsconfig looks like this:

{
  "compilerOptions": {
    "declaration": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "lib": ["es7", "dom", "esnext"],
    "module": "es6",
    "moduleResolution": "node",
    "sourceMap": true,
    "target": "es6",
    "jsx": "react",
    "esModuleInterop": true
  },
  "exclude": ["node_modules", "vendor", "public", "test"],
  "compileOnSave": false
}

My package.json has the following test script:

  "scripts": {
    "test": "TS_NODE_PROJECT='./tsconfig.json' mocha -r ts-node/register -r esm test/**/*.ts"
  },

Is this because mocha runs on NodeJS, which require files to explicitly declare exports/imports?

Refactoring the types.ts files to explicitly import/export their types is not currently an option - we have many intertwined types, and updating each file to contain imports/exports would involve touching almost every file in the codebase - definitely a longer term project to tackle.

Answer 1

Assuming your tsconfig is used for the tests only you can tell ts-node to include custom types:

In tsconfig.json

{
  "ts-node": {
    "files": true
  },
  "compilerOptions": {
    "declaration": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "lib": ["es7", "dom", "esnext"],
    "module": "es6",
    "moduleResolution": "node",
    "sourceMap": true,
    "target": "es6",
    "jsx": "react",
    "esModuleInterop": true
  },
  "exclude": ["node_modules", "vendor", "public", "test"],
  "compileOnSave": false,
  "files": ["Pills/types.ts"] // WHere you keep the types
  "include": ["test/**/*.ts"] // Wherever you keep your tests
}